1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
|
//===-------------------------- random.cpp --------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#if defined(_WIN32)
// Must be defined before including stdlib.h to enable rand_s().
#define _CRT_RAND_S
#include <stdio.h>
#endif // defined(_WIN32)
#include "random"
#include "system_error"
#if defined(__sun__)
#define rename solaris_headers_are_broken
#endif // defined(__sun__)
#if !defined(_WIN32)
#include <fcntl.h>
#include <unistd.h>
#endif // !defined(_WIN32)
#include <errno.h>
#if defined(_LIBCPP_USING_NACL_RANDOM)
#include <nacl/nacl_random.h>
#endif // defined(_LIBCPP_USING_NACL_RANDOM)
_LIBCPP_BEGIN_NAMESPACE_STD
#if defined(_WIN32)
random_device::random_device(const string&)
{
}
random_device::~random_device()
{
}
unsigned
random_device::operator()()
{
unsigned r;
errno_t err = rand_s(&r);
if (err)
__throw_system_error(err, "random_device rand_s failed.");
return r;
}
#elif defined(_LIBCPP_USING_NACL_RANDOM)
random_device::random_device(const string& __token)
{
if (__token != "/dev/urandom")
__throw_system_error(ENOENT, ("random device not supported " + __token).c_str());
int error = nacl_secure_random_init();
if (error)
__throw_system_error(error, ("random device failed to open " + __token).c_str());
}
random_device::~random_device()
{
}
unsigned
random_device::operator()()
{
unsigned r;
size_t n = sizeof(r);
char* p = reinterpret_cast<char*>(&r);
size_t bytes_written;
int error = nacl_secure_random(&r, n, &bytes_written);
if (error != 0)
__throw_system_error(error, "random_device failed getting bytes");
else if (bytes_written != n)
__throw_runtime_error("random_device failed to obtain enough bytes");
return r;
}
#else // !defined(_WIN32) && !defined(_LIBCPP_USING_NACL_RANDOM)
random_device::random_device(const string& __token)
: __f_(open(__token.c_str(), O_RDONLY))
{
if (__f_ < 0)
__throw_system_error(errno, ("random_device failed to open " + __token).c_str());
}
random_device::~random_device()
{
close(__f_);
}
unsigned
random_device::operator()()
{
unsigned r;
size_t n = sizeof(r);
char* p = reinterpret_cast<char*>(&r);
while (n > 0)
{
ssize_t s = read(__f_, p, n);
if (s == 0)
__throw_system_error(ENODATA, "random_device got EOF");
if (s == -1)
{
if (errno != EINTR)
__throw_system_error(errno, "random_device got an unexpected error");
continue;
}
n -= static_cast<size_t>(s);
p += static_cast<size_t>(s);
}
return r;
}
#endif // defined(_WIN32) || defined(_LIBCPP_USING_NACL_RANDOM)
double
random_device::entropy() const _NOEXCEPT
{
return 0;
}
_LIBCPP_END_NAMESPACE_STD
|